1 / 25

Landsat MSS update to Science Team

Landsat MSS update to Science Team. 19 January 2010. MSS migration to LPGS highlights. Objective:Create cheaper, better MSS L1T products in a format and with metadata that are compatible with TM and ETM+

herschel
Download Presentation

Landsat MSS update to Science Team

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Landsat MSS update to Science Team 19 January 2010

  2. MSS migration to LPGS highlights • Objective:Create cheaper, better MSS L1T products in a format and with metadata that are compatible with TM and ETM+ • Cross-calibration gains, biases, and time dependent variables are used to map the MSS archive data to radiance using the Normalized Radiance method developed at SDSU. • Hierarchical (Gaussian Pyramid) image matching • Geometric verification

  3. Hierarchical Image Registration Module • Gaussian Pyramid based image registration for approximation determination • Refinement using the existing correlation techniques and GLS 2000 GCP chips • Does Hierarchical Image Matching perform as expected? • Yes. We are seeing automated results in cases where NLAPS needed operator assistance with initial control selection. • It has matched test scenes that were are far as 10km off (MSS-X) • Limitations: Winter scenes (full snow cover) did not perform well at the highest pyramid levels (lowest resolution). • System Tests for MSS-P, prior to refinement of parameters, show 24 of 70 images with less than 1-pixel RMSE using independent verification • Should also improve initial location determination for Landsat TM

  4. MSS verification example Path/Row : 36/37 (WRS-1) Legend : Green - RMSE <= 0.5 pixel Cyan - 0.5 < RMSE <= 1 pixel Blue - 1 < RMSE <= 2 pixel Yellow - 2 < RMSE <= 3 pixel Red - RMSE > 3 pixel RMSE by quadrant and scene UL: 0.33 pixel UR: 0.41pixel LR: 0.43 pixel LL: 0.44 pixel SCENE: 0.41 pixel stored in metadata file (MTL) Rules 50 by 50 grid Strength of correlation Distance from other points RMSE Verification report contains summary statistics and a list of all verification points.

  5. MSS verification example Path/Row : 36/37 (WRS-1) Legend : Green - RMSE <= 0.5 pixel Cyan - 0.5 < RMSE <= 1 pixel Blue - 1 < RMSE <= 2 pixel Yellow - 2 < RMSE <= 3 pixel Red - RMSE > 3 pixel RMSE by quadrant and scene UL: 0.77 pixel UR: 1.17 pixel LR: 0.96 pixel LL: 0.97 pixel SCENE: 0.97 pixel stored in metadata file (MTL) Rules 75 by 75 grid Strength of correlation RMSE Distance from other points Verification report contains summary statistics and a list of all verification points.

  6. MSS-X/A Destripe Destriping of MSS data is an acknowledged requirement. Initially the legacy histogram equalization destripe will be implemented. A task for 2010 is to analyze the impact of destripe on radiometric calibration.

  7. Landsat MSS “Orphans” • What are they? • Wide Band Video images for which imagery exists, but no ephemeris • Issue • During the Wide Band Video recovery program about 244,000 images, of which about 150,000 are unique, could not be processed due to a lack of ephemeris • Solution • Use orbit dynamics model to generate estimated ephemeris • MSS migration to LPGS with it’s more robust registration model should be tolerant of imagery with large initial locational errors.

  8. Landsat MSS Products • L0R • MSS-X, MSS-A, MSS-P • L0Rp • HDF output of reformatter • L1G • Registration failed to meet RMSE threshold needed for terrain correction. • Fail in hierarchical pyramid correlation or precision control matching • Registered, but failed in verification module. • L1T • Precision- and Terrain-corrected Product

  9. Landsat MSS release notes • A mixed archive (NLAPS & LPGS) will exist through the transition period: • A user will receive either LPGS or an NLAPS MSS format product. • Same issue with TM-A, which will follow MSS release. • We will flush all MSS-P NLAPS products from the system prior to MSS-P release (3/2010). • Likewise for MSS-X (7/2010) and MSS-A (9/2010) releases. • Inevitability some LPGS images will fall back to L1G, even though they previously processed to L1T with manual intervention. • The new metadata and image format for MSS will be compatible with other LPGS L1T products. • However initially opening the MSS L1T in COTS may fail. For example, ENVI hangs if their Landsat with metadata input function is used – it expects a TM image. • All MSS sensors are cross-calibrated to MSS-5, so reflectance calculations need to use MSS-5 parameters for ESUN. • Once we get the system tests completed (late February), example products and documentation will be placed on the website for examination so users and vendors can adapt their processing flows. • We will ultimately have a consistent, cross-calibrated archive of Landsat data. • We are trending all products and expect to be able to improve the quality. We expect to reprocess MSS products.

  10. Landsat Full-Resolution Browse 19 January 2010

  11. LDCM Full-Resolution Browse • Browse images will be created for quick and efficient image selection and for visual interpretation. The following three criteria are critical to meet user needs for browse images: • Provide a browse that is geo-registered and GIS-ready • Provide full spatial resolution browse for local area evaluation • Provide small browse definition for quick delivery, particularly for large areas, over the Internet, and for creation of page-size graphics • There may be up to five browse files associated with each scene: • Reflective OLI full resolution JPEG image: 3 band, 8-bits per band • Reflective OLI reduced resolution JPEG image: a reduced resolution version of the reflective full resolution browse • Thermal TIRS full resolution JPEG image: 1 band, 8-bit grayscale • Thermal TIRS reduced resolution JPEG image: a reduced resolution version of the thermal full resolution browse • Quality band PNG: a color mapped version of the quality band – future activity for Landsat 1-7

  12. Full-Resolution Reflective Browse • Band combinations – “Green” • OLI: 6,5,4 • ETM+ & TM: 5,4,3 • MSS: 2,4,1 • Data values • Top of Atmosphere Reflectance • 0 - 0.8 stretched to 0 - 255 • Image format • 3-band RGB JPEG • Georeference information in World & GDAL XML files • JPEG and georeference files zipped for download • File size is approximately 5 MB • Pixel size is retained http://picasaweb.google.com/soapnut

  13. Reflective TM & ETM+ Browse • Llaima volcano, Chile • Craters of the Moon, Idaho • Bands 543 • TOA reflectance 14 July 2009 18 April 2009 10 July 1996

  14. Reflective MSS Browse • Desert, Everglades, Miami • Bands 241 (“Green”) - TOA reflectance with 0.8 clip is planned, shown here as TOA radiance with 2% clip Landsat 3 MSS 9 March1979 Landsat 2 MSS 12 June 1980

  15. Full-Resolution Thermal Browse • Band combinations • TIRS • TM: Band 6 • ETM+: Band 61 (low gain) • MSS: None • Data values • Top of Atmosphere Brightness Temperature • -40 °C to 50 °C stretched to 0 – 255 or 2% clip • Image format • Gray-scale JPEG • Georeference information in World & GDAL XML file • JPEG and georeference files zipped for download • File size is approximately 2 MB • Pixel size is retained

  16. Thermal TM & ETM+ Browse -40 °C to 50 °C clip with linear stretch 2% clip with linear stretch • Band 6 • TOA Brightness Temperature Craters of the Moon, Idaho Landsat 5 TM 10 July 1996 Llaima Volcano, Chile Landsat 7 ETM+ 18 April 2009

  17. Watermarked browse

  18. Production and Distribution • Created from L1T data • All files stored online indefinitely • Available for use by web services • Available for use by EarthExplorer and Glovis • Available for download using Bulk Tool • Download individual browse JPEG images and bundled suite of GIS-ready browse images on-demand as Zip file • EarthExplorer • Glovis

  19. Rationales • Compatibility with LDCM • TOA reflectance with fixed scale • Images more comparable through time and space • TOA brightness temperature with 2% or fixed scale TBD • Format • Georeference information distributed as separate files • Compressed GeoTIFF and JPEG2000 are not well supported by web or analysis tools

  20. 30-meter Thermal 19 January 2010

  21. Landsat TM & ETM+ Thermal • Objectives • Provide “analysis-ready” 30-meter product that does not require resampling to match other Bands • Minimize introduction of radiometric artifacts • Resist approach that disguises native resolution • Minimize time to implementation • Provide methodology that can be reused for LDCM TIRS • Current approach • CC resampling based on 60-meter (ETM+) or 120-meter (TM) postings in input space • Output with 60-meter pixel size • Corner point geometry is ambiguously applied in COTS resulting in shifts between thermal and reflective bands

  22. Thermal Band: 30m • Requested at January 2009 Science Team meeting • Help with thermal band offsets from the multispectral • COTS package interpretations of resolution mismatch • June 2009 Science Team at confirmation to proceed @ June meeting The USGS Landsat processing system references pixel centers to coordinates, which causes an offset in commercial software packages. The blue frame represents 30-meter Landsat 7 multispectral pixels, while the red frame represents the 60-meter Landsat 7 thermal pixels. (R. Allen, 2009)

  23. Evaluation • Landsat developed test products • Evaluated by Rick Allen & team a resampled to 30 m using NLAPS with Nearest Neighbor resampling resampled to 60 m using LPGS with cubic convolution resampling resampled to 30 m using LPGS with cubic convolution resampling The thermal band from the path 40 row 30 image from July 10 1996 DN 130-165 red through yellow; DN 165-200 yellow through green. (R. Allen, 2009) • Resample to 60 meter from 120 meter TM thermal data is existing product • Resample to 30 meter from either 120-meter TM or 60-meter ETM+ using CC in input space can be implemented with a parameter change

  24. Two other alternatives among many • Resampling to native cell size (TM 120- or ETM+ 60-meter) with cubic convolution, then replicate pixels to 30-meter • Estimated to have minimal implementation costs • Fewest artifacts, such as ringing • Reversible to native resolution • Resample to 30-meter pixels with cubic convolution on 30-meter postings in output space • Higher implementation costs • Impacts less well understood • Similar to replication to 30-meter pixels then resample with cubic convolution Resampled to 120 m using cubic convolution, then replicated pixels to 30 m

  25. Approaches • Approach evaluated by Allen and team • Configuration change: 2 days to execute • More complex approach • Research requirement • Code changes in Image Assessment System (IAS) & Level-1 Product Generation System (LPGS) • Competes with other high priority tasks, such as MSS, for resources • Leads toward LDCM solution • Revisit GeoTIFF area versus point issues with vendors • Needed for pan

More Related